Return to aors.h CVS log

Up to [local] / OpenXM_contrib / gmp / mpz

Annotation of OpenXM_contrib/gmp/mpz/aors.h, Revision 1.1.1.1

1.1       ohara       1: /* mpz_add, mpz_sub -- add or subtract integers.
                      2:
                      3: Copyright 1991, 1993, 1994, 1996, 2000, 2001 Free Software Foundation, Inc.
                      4:
                      5: This file is part of the GNU MP Library.
                      6:
                      7: The GNU MP Library is free software; you can redistribute it and/or modify
                      8: it under the terms of the GNU Lesser General Public License as published by
                      9: the Free Software Foundation; either version 2.1 of the License, or (at your
                     10: option) any later version.
                     11:
                     12: The GNU MP Library is distributed in the hope that it will be useful, but
                     13: WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
                     14: or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
                     15: License for more details.
                     16:
                     17: You should have received a copy of the GNU Lesser General Public License
                     18: along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
                     19: the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
                     20: MA 02111-1307, USA. */
                     21:
                     22: #include "gmp.h"
                     23: #include "gmp-impl.h"
                     24:
                     25:
                     26: #ifdef BERKELEY_MP
                     27:
                     28: #include "mp.h"
                     29: #ifdef OPERATION_add
                     30: #define FUNCTION     madd
                     31: #define VARIATION
                     32: #endif
                     33: #ifdef OPERATION_sub
                     34: #define FUNCTION     msub
                     35: #define VARIATION    -
                     36: #endif
                     37: #define ARGUMENTS    mpz_srcptr u, mpz_srcptr v, mpz_ptr w
                     38:
                     39: #else /* normal GMP */
                     40:
                     41: #ifdef OPERATION_add
                     42: #define FUNCTION     mpz_add
                     43: #define VARIATION
                     44: #endif
                     45: #ifdef OPERATION_sub
                     46: #define FUNCTION     mpz_sub
                     47: #define VARIATION    -
                     48: #endif
                     49: #define ARGUMENTS    mpz_ptr w, mpz_srcptr u, mpz_srcptr v
                     50:
                     51: #endif
                     52:
                     53: #ifndef FUNCTION
                     54: Error, need OPERATION_add or OPERATION_sub
                     55: #endif
                     56:
                     57:
                     58: void
                     59: FUNCTION (ARGUMENTS)
                     60: {
                     61:   mp_srcptr up, vp;
                     62:   mp_ptr wp;
                     63:   mp_size_t usize, vsize, wsize;
                     64:   mp_size_t abs_usize;
                     65:   mp_size_t abs_vsize;
                     66:
                     67:   usize = u->_mp_size;
                     68:   vsize = VARIATION v->_mp_size;
                     69:   abs_usize = ABS (usize);
                     70:   abs_vsize = ABS (vsize);
                     71:
                     72:   if (abs_usize < abs_vsize)
                     73:     {
                     74:       /* Swap U and V. */
                     75:       MPZ_SRCPTR_SWAP (u, v);
                     76:       MP_SIZE_T_SWAP (usize, vsize);
                     77:       MP_SIZE_T_SWAP (abs_usize, abs_vsize);
                     78:     }
                     79:
                     80:   /* True: ABS_USIZE >= ABS_VSIZE.  */
                     81:
                     82:   /* If not space for w (and possible carry), increase space.  */
                     83:   wsize = abs_usize + 1;
                     84:   if (w->_mp_alloc < wsize)
                     85:     _mpz_realloc (w, wsize);
                     86:
                     87:   /* These must be after realloc (u or v may be the same as w).  */
                     88:   up = u->_mp_d;
                     89:   vp = v->_mp_d;
                     90:   wp = w->_mp_d;
                     91:
                     92:   if ((usize ^ vsize) < 0)
                     93:     {
                     94:       /* U and V have different sign.  Need to compare them to determine
                     95:         which operand to subtract from which.  */
                     96:
                     97:       /* This test is right since ABS_USIZE >= ABS_VSIZE.  */
                     98:       if (abs_usize != abs_vsize)
                     99:        {
                    100:          mpn_sub (wp, up, abs_usize, vp, abs_vsize);
                    101:          wsize = abs_usize;
                    102:          MPN_NORMALIZE (wp, wsize);
                    103:          if (usize < 0)
                    104:            wsize = -wsize;
                    105:        }
                    106:       else if (mpn_cmp (up, vp, abs_usize) < 0)
                    107:        {
                    108:          mpn_sub_n (wp, vp, up, abs_usize);
                    109:          wsize = abs_usize;
                    110:          MPN_NORMALIZE (wp, wsize);
                    111:          if (usize >= 0)
                    112:            wsize = -wsize;
                    113:        }
                    114:       else
                    115:        {
                    116:          mpn_sub_n (wp, up, vp, abs_usize);
                    117:          wsize = abs_usize;
                    118:          MPN_NORMALIZE (wp, wsize);
                    119:          if (usize < 0)
                    120:            wsize = -wsize;
                    121:        }
                    122:     }
                    123:   else
                    124:     {
                    125:       /* U and V have same sign.  Add them.  */
                    126:       mp_limb_t cy_limb = mpn_add (wp, up, abs_usize, vp, abs_vsize);
                    127:       wp[abs_usize] = cy_limb;
                    128:       wsize = abs_usize + cy_limb;
                    129:       if (usize < 0)
                    130:        wsize = -wsize;
                    131:     }
                    132:
                    133:   w->_mp_size = wsize;
                    134: }